Association of host plant growth and weed occurrence with armyworm(Mythimna separata) damage in corn fields

To clarify association between armyworm（Mythimna separata） damage level and the corn growth and weed occurrence, we investigated corn plant height, stem diameter and vigor as well as weed coverage and biomass. The investigations were conducted at three locations of Shaanxi Province, China which were suffered seriously from armyworm. Significant correlations were found between the parameters analyzed. At stunted corn growth and presence of plenty of weeds, the armyworm damage tended to be heavy; oppositely, when corn grew well and weed density were low, armyworm harm was the minimal. Therefore, corn growing status and weed density can significantly affect armyworm damage level. Our results imply that promoting corn growth and timely removal of weeds are conducive to reducing armyworm occurrence.

Control Effects of 3 Kinds of Herbicides against Weeds in Dogbane (Apocynum venetum) Field

[ Objective] The paper was to explore the control effects of 3 kinds of herbicides against weeds in dogbane （Apocynum venetum） field. [ Method ] Using haloxyfop-R-mithyl and quizalofop-ethyl EC specifically killing monagenns gramineous weeds and chipton specifically killing dicotyledonous broad-leaf weeds, the control test against weeds in 2-year-old dogbane field was carried out. [ Result ] Haloxyfop-R-mithyl had good control effect against gramincous weeds, and its control effect against both barnyard weed （ Echinochloa crusgalli） and green bristleweed （ Setaria viridis ） was greater than 35.0% ; the control effects of quizalofop- ethyl EC against barnyard weed and green bristleweed were 14.8% and 28.6%, respectively; chipt0n had good control effect against Chenopodium album, and the control effect reached 30.8%. Moreover, 3 herbicides did not cause damage to dogbane. [ Conclusion] The study provide theoretical basis for completing cultivation technique of dogbane.

Study on Analysis Model of Millet Yield Loss Caused by Weeds in Summer Season Millet Field

Weed management in summer season foxtall millet field was studied by evaluating weed damage and exploring competition between weeds and foxtail millet, and a few fitting models were simulated and compared by employing field plot experiment and nonlinear regression analysis. The results showed that the millet yield losses and weed density were extremely significantly correlated. Among the tested models, the determination coefficient （ R2 ） of hyperbolic model was 0.997 12, and minimum residual sum of squares was 16.174, which was considered the optimal model to simulate the competition relation between weeds and millet. The predicted equation was Y = d/（ 1. 733 ＋ 0. 018d） ; the interspecific competitiveness of weeds was 0. 577 0 and the intraspecific competitiveness was 0.010 3 ; the maximum loss rate of millet yield was 55.56%. This study had established an analysis model with high gcodness-of-fit and practical prediction which could help weed management in summer season millet field.

Effects of Paddy Field Rotation on Diseases,Pests and Weeds of Rice

[ Objective] The paper was to explore ecological effect of paddy field rotation on reducing disease, pests and weeds of rice. [ Method] With long-term continuous cropping rice as control, according to field location experiments for consecutive 14 years, the effects of paddy field rotation on diseases, pests and weeds of rice were studied in details. [ Result] Paddy field rotation in some extent could reduce diseases, pests and weeds of rice. The diseased plant rate and disease in- dex of rice sheath blight in early rice under paddy field rotation treatment were averagely 10% and 0.4% lower than those in continuous cropping treatment, respec- tively. The diseased plant rate and disease index of rice sheath blight in late rice were 17.7% and 13.3% lower than those in treatments with continuous cropping mode, respectively. The diseased plant rate and disease index of rice false smut in both early rice and late rice under rotation treatments were lower than those in treatments with continuous cropping mode. White leaf rate caused by rice leaf roller and dry heart rate caused by striped rice borer under rotation treatments were significantly lower than those under continuous cropping treatment. The growth status of weeds under rotation treatments was weaker than that under continuous cropping treatment. [ Conclusion] The paper has important significance on alleviating diseases, pests and weeds of rice and improvement of ecological environment of farmland, and provides theoretical basis for sustainable development of agriculture.

Chemical Weeding in Dry Direct Seeding Fields of Single Cropping Middlelate Rice

Chemical weeding in dry direct seeding fields of single cropping middle-late rice was studied in Huida vegetable farm of Huizhou City in 2012. The main treatment was herbicide（ pretilachlor ＋ bensulfuron-methyl,Yangguo and butachlor）,and the sub-treatment was application method（ soil treatments,seedling treatment and integrated treatment）. The results showed that 80 g pretilachlor ＋ bensulfuron-methyl（ 36% pretilachlor ＋ 4% bensulfuron-methyl） diluted with 50 kg water could be sprayed or 200 g Yangguo（ 23. 9% butachlor ＋ 1. 1% bensulfuron-methyl） mixed with 15 kg sandy soil could be broadcasted per 667 m2 on the sowing day or the second day under moist condition of soil,which could effectively control weeds in dry direct seeding fields of single cropping middle-late rice.

Enhanced Species Diversity Unlocked by Habitat Conservation in Agricultural Landscapes: New Perspectives on Ecological Weed Management and Sustainable Intensification—Species Diversity and Habitat Conservation

The impulse to remain profitable by increasing agricultural production levels in view of the greater demand for food, provided impetus to production intensification. The aim of this review is to summarise current literature, reporting specifically on the impact of production intensification on habitats and yield constraints caused by weeds. Secondly, in alleviating these effects over the short term, ecological measures that enhance species diversity in conserved habitats and promote semi-natural habitats in the agricultural landscape, are discussed. In large-scale intensive agriculture, weed control is predominantly rooted in agrochemical applications in the form of herbicides. Long lasting intensive agricultural practices show discord both with the promotion of the biodiversity of microbes belowground and aboveground and with organisms involved in the breaking down of plant material. The presence of native species in the surroundings, in combination with hedgerows and field margins, with a comparatively intricate and balanced variety of plants in a sheltered environment, are essential for settlement of benign insects, particularly in the face of intensive agricultural production. The promising tactic of advantageous seed predators enables decreased herbicide applications. Crop mosaics arranged to advance compatibility at the landscape scale are important to bolster pollination services and insect management, while ecological variety in the surroundings acts as a safety net for habitat diversity. Weed control in combination with different tactics of vegetation use, comprising cover cropping, hedgerows and field margins, sets up safe havens in the landscape, and improves the diffusion of complementary life forms. Field margins perform a meaningful natural function as point of provision for forage, safe havens and distribution passageways for pollinators and insect predators. Production practices that promote more heterogeneity and combine high density semi-natural safe havens and habitat conservation in agro ecosystems are beneficial to species diversity across trophic levels and contribute to agricultural production stability and food safety.

Evaluation of soil flame disinfestation(SFD) for controlling weeds,nematodes and fungi

Soil flame disinfestation(SFD) is a form of physical disinfestation that can be used both in greenhouses and on field crops. Its use for soil disinfestation in different crop growing conditions makes it increasingly attractive for controlling soilborne pathogens and weeds. But little is known about the effect on weeds and soilbrone diseases. This study reports on greenhouses and field crops in China that determined the efficacy of SFD to control weeds, nematodes and fungi. It also determined the impact of SFD on the soil physical and chemical properties(water content, bulk density, NO3^–-N content, NH4^+-N content, conductivity and organic matter) in three field trials. A second generation SFD machine was used in these trials. SFD treatment significantly reduced weeds(>87.8%) and root-knot nematodes(Meloidogyne incognita)(>98.1%). Plant height and crop yield was significantly increased with SFD treatment. NO3^–-N and NH4^+-N increased after the SFD treatment, and there was also an increase in soil conductivity. Water content, bulk density and organic matter decreased significantly in the soil after the SFD treatment compared to the control. Soil flame disinfestation is a potential technique for controlling weeds and diseases in greenhouses or in fields. SFD is a non-chemical, safe, environmentally-friendly soil disinfection method.

Preparation of 55% MCPA-isooctyl and Ametryn EC and Its Field Efficacy

[ Objective] The purpose was to supply experimental base for preparing new types of high efficient and safe mixture herbicide for sugarcane field. [ Method ] The associated function of MCPA-isooctyl and ametryn on Digitaria sanguinalis and Celosia argentea was evaluated by co-tox. icity coefficient method by potting experiment. [ Result] When active ingredient of MCPA-isooctyl and ametryn was mixed in the proportion of 9： 5, there was obvious synergistic effect on D. sanguinalis and C. argentea, while the co-toxicity coefficients reached 156.24 and 140.40. Proportion method and bisection method were used to confirm the optimum proportion of various ingredients in mixture of MCPA-isooctyl and ametryn, and the optimum proportion was as follows： 35.4% MCPA-isooctyl, 19.6% ametryn, 10.0% emulsifier and the rest were solvents. The stability test indicated that each index of this EC was consistent with standard for pesticide EC. Field efficacy test of 55% MCPA-isooctyl and ametryn EC showed that most weeds in sugarcane field could be effectively controlled with the dose range of 1 073 -2 310 g （a. i. ）/hm^2. [ Conclusion ] Mixture product of ametryn and MCPA-isooctyl with high content was successfully developed, which had the advantages including high efficiency, broad spectrum, good economy and convenient utilization, etc.

Development and Fabrication of Manually Push-Pull Type Conical Weeder for Bangladesh Condition

In Bangladesh, the use of machinery in agriculture production is fast rising. Researchers are developing technology to replace traditional hand weeding to manage weeds in rice fields. The present study has been taken to increase weeding efficiency and reduce the drudgery in weeding and mulching. A line-to-line distance of 20 cm, the operation is push-pull, and field operating condition at 2 - 4 cm standing water (for softening the field) was the designed hypothesis. The weeder consists of a skid/float, float holder, float adjuster, main body frame, rotor, axel, bush, rotor holder, rotor holder adjuster, handle, handle griper, handle holder, handle height adjuster, nut, bolt, etc. The designed weeder was fabricated using MS sheet, MS pipe, MS flat bar, MS nut-bolt, etc. When the rotors perform back and forth, the weeder’s two conical rotors with six plain blades and six serrated blades work together to uproot and bury the weeds. It also contains a 2 mm thick float assembly with a precise angle of 22 degrees. Weeds are uprooted by the weeder’s blades and buried in the muddy soil. It causes topsoil disturbance and enhances aeration. The weeding efficiency and capacity of the conical weeder were 81.92% and 0.0203 ha/h respectively. With a push-pull operation, the weeder can uproot and bury the weeds in a single row at a time. The pushing force and weight of weeder were 43.42 N and 5.6 kg respectively. Farmers can use this weeder to increase their comfort and reduce the drudgery associated with weeding and mulching in their fields.

Effects of the inhibition of weed communities by winter-flooding

Winter-flooded paddy field is an agricultural method which putting a water among the winter, it is paid attention as an environmental friendly agriculture. Especially, it is said, winter-flooding is control paddy weeds and there is the farming potential that the annual rice yield is high. However, there is no detailed research about the effects of weed communities by winter-flooding, as the purpose of this study, we investigated the effects of the inhibition of weed communities (life cycle, harmful weed) by winter-flooding at a shore of Inba Lake, Chiba Prefecture, Japan, and compared them to paddy weeds in a dry paddy field. Methods examined the plant height (cm) and the cover degree class of all appearance species in each quadrant frame (1 m2). Quadrant in the two type paddies were 10 frames (D1-D10) at the control, and were 10 frames (W1-W10) at the treatment (Figure 1). In a winter-flooded paddy field, species number and plant volume of winter-annual plants decreased in the third winter after winter-flooding, In particular, the plant volume of Alopecurus aequalis, Cardamine flexuosa decreased significantly. We considered that the cause of this decrease was due to the depth of flooding (more than 10 cm). Eleocharis kuroguwai and Echinochloa oryzoides, which are perennial plants, Sagittaria trifolia, which is an annual plant, increased in a winter-flooded paddy field in the third summer after winter-flooding. We considered that these species grew thicker at places where the seeds germinated, and grew easily, because the conservation situation of the seeds fitted well under the winter-flooding conditions. They started to grow immediately after the drainage of water. The period of drainage coincided with increasing light intensity and temperature. In addition, the annual rice yield of the third year after winter-flooding was higher than that of the habitual practice rice field.

毕节山地玉米田间杂草种类及危害程度调查

为明确毕节山地玉米种植区田间杂草的组成以及群落结构特征,采用倒置“W”九点取样法于2023年7月对毕节地区的玉米田杂草发生种类及危害情况进行调查。结果表明,毕节地区玉米田杂草184种,隶属于47科140属,其中双子叶杂草153种,单子叶杂草31种,分别占样方中杂草种类的83.16%和16.84%。优势杂草主要有菊科(共37种,占20.11%)、禾本科(共24种,占13.04%)、蓼科(共16种,占8.70%);通过优势度分析,相对多度最大的是升马唐,为31.49,其次是粗毛牛膝菊和狗尾草,分别为28.43和27.69。发生广泛且危害严重的有粗毛牛膝菊、升马唐、狗尾草、繁缕、鬼针草;其次是腺梗豨莶、细柄野荞麦、阿拉伯婆婆纳、尼泊尔蓼、野艾蒿、酢浆草、铁苋菜、裂苞铁苋菜、藜、打碗花、小蓬草、牛筋草、野草香、反枝苋和续断菊。

几种除草剂对麦田阔叶杂草的防除效果

为明确几种除草剂对小麦田阔叶杂草的防除效果及对小麦的安全性,于返青期采用茎叶喷雾法,选取30%氰草津SC、10%唑嘧磺草胺SC、40%砜吡草唑SC、86%2甲4氯异辛酯EC+480 g/L灭草松AS、16%吡酰草·双氟草SC、5%双氟磺草胺OD、28.8%氯氟吡氧乙酸EC等7种药剂进行大田药效试验,测定其对猪殃殃、播娘蒿、荠菜等杂草的防除效果。结果表明,86%2甲4氯异辛酯EC+480 g/L灭草松AS、16%吡酰草·双氟草SC对总杂草的防效最好,药后45 d鲜重防效分别为93.05%和95.65%。30%氰草津SC、40%砜吡草唑SC对杂草的防除效果较差,药后45 d鲜重防效分别为51.51%、42.58%,但对于以葎草为主的延迟出土类杂草有较好的封闭效果。28.8%氯氟吡氧乙酸EC、86%2甲4氯异辛酯EC+480 g/L灭草松AS处理的小麦有药害产生,可能与施用苯醚甲环唑防治病害有关。其他处理对小麦生长无明显不良影响。可见,这7种除草剂对阔叶杂草防效的差异较大。相比其他单剂,86%2甲4氯异辛酯EC 387.0 g/hm^(2)+480 g/L灭草松AS 720.0 g/hm^(2)、16%吡酰草·双氟草SC 120.0 g/hm^(2)对各种杂草表现出优异的防效,在小麦返青期茎叶喷雾处理防除一年生阔叶杂草有较为良好的应用前景。

直播方式对重庆地区稻田杂草群落组成和生态位的影响

为高效绿色防除重庆地区直播稻田杂草,对淹水直播和湿润直播处理下稻田杂草的群落组成和生态位进行研究。结果表明,淹水直播和湿润直播稻田的杂草群落分别由16种(隶属于9科15属)和18种(隶属于10科17属)杂草组成,水蓼(Polygonum hydropiper)和鬼针草(Bidens pilosa)为湿润直播下特有的杂草。淹水直播和湿润直播的重要杂草群落结构分别为丁香蓼(Ludwigia prostrata)+鸭舌草(Monochoria vaginalis)+稗草(Echinochloa crus-galli)和陌上菜(Lindernia procumbens)+稗草(E.crus-galli)+看麦娘(Alopecurus aequalis)+异型莎草(Cyperus difformis)。除稗草(E.crus-galli)外,两种直播方式下重要杂草的重要值均差异显著(P<0.05)。两种直播方式共有的14种重要或主要杂草中,淹水直播下光头稗(Echinochloa colonum)、稗草、异型莎草、陌上菜、看麦娘、笄石菖(Juncus prismatocarpus)、双穗雀稗(Paspalum distichum)共7种重要或主要杂草的生态位宽度较湿润直播下显著降低,且其种间(除笄石菖与双穗雀稗外)生态位叠加值或显著降低或持平。综上,淹水直播可抑制水蓼和鬼针草的萌发,从而改变稻田重要杂草的群落结构,而且可控制光头稗、稗草、异型莎草、陌上菜、看麦娘、笄石菖、双穗雀稗的数量。

基于药草比控制的中药材田间杂草防除措施初探

杂草是农业生态系统的重要组成部分。中药生态农业倡导中药材仿野生种植和拟境栽培种植模式,种植过程中,保留一定数量的杂草,尤其是野生群落中常见的伴生杂草,最大程度地模拟原生态环境,从而提升中药材产量和品质,提高栽培中药材的经济效益。以中药生态农业关于杂草防控理论为指导思想,探讨了基于药草比控制的中药材栽培田间杂草控制措施;同时以甘草为例,探讨了栽培甘草整个生育期杂草最佳防除频率。结果表明:每隔28 d除一次杂草的甘草品质最佳,经济效益最高。这种杂草防除措施可使甘草与杂草在密度、多样性和盖度方面的配比达到最佳平衡值,这为今后中药材仿野生种植和逆境栽培种植过程中杂草防除拓宽了研究思路。

洁田稻稻田杂草防控及杂草稻种群耐药性研究

为探索咪唑啉酮类除草剂对洁田稻稻田常规杂草和杂草稻的防治效果及不同杂草稻种群对咪唑乙烟酸的耐药性,采用大田试验在不同时期喷施不同浓度的咪唑乙烟酸水剂防治田间不同杂草及室内盆栽试验鉴定杂草稻耐药性。结果表明:咪唑乙烟酸在水稻播后20 d施用,对田间杂草稻具有较好的防效,1 200 mL·hm^(-2)咪唑乙烟酸对田间杂草稻的防效达92.8%。过早施药对杂草稻防效普遍低于90%,过晚施药需加大剂量才能达到较好的防效。咪唑乙烟酸供试中、高浓度对稗草和千金子具有较好的防效,而对多花水苋和丁香蓼等阔叶杂草防效较差。耐药性鉴定结果表明,不同区域的杂草稻种子对咪唑乙烟酸较敏感,未产生明显的耐药性。

不同控草方式对花椒地杂草生长及土壤养分的影响

为明确花椒地不同控草方式对杂草生长的影响,在遵义市红花岗区花椒基地设置4种不同控草措施(处理),即:除草剂(T1)、鼠茅草(T2)、防草布(T3)、秸秆覆盖(T4),以自然生草作为对照(CK),对比分析不同控草方式对花椒地杂草种类、数量、生物量以及土壤肥力的影响,评估不同处理的控草效果。结果表明:花椒地共出现杂草种类26种,归属16个科;4个处理均对花椒地杂草起到了不同程度的抑制效果,其中T3效果最好,仅发现4种杂草,较CK减少10种,且杂草密度和生物量均为最低,株防效和生物量防效均超过了97%;T2次之,株防效和生物量防效在5月超过了60%,在7月超过了80%;T1与T4在后期效果差;4个处理中仅T4对土壤肥力有明显的提升效果,其他处理未产生显著影响。综合来看,防草布覆盖、间种鼠茅草2种控草方式可作为遵义地区花椒地的控草技术进行应用。

基于ViT-改进YOLOv7的稻田杂草识别

为解决光线遮蔽、藻萍干扰以及稻叶尖形状相似等复杂环境导致稻田杂草识别效果不理想问题,该研究提出一种基于组合深度学习的杂草识别方法。引入MSRCP(multi-scale retinex with color preservation)对图像进行增强,以提高图像亮度及对比度;加入ViT分类网络去除干扰背景,以提高模型在复杂环境下对小目标杂草的识别性能。在YOLOv7模型中主干特征提取网络替换为GhostNet网络,并引入CA注意力机制,以增强主干特征提取网络对杂草特征提取能力及简化模型参数计算量。消融试验表明:改进后的YOLOv7模型平均精度均值为88.2%,较原YOLOv7模型提高了3.3个百分点,参数量减少10.43 M,计算量减少66.54×109次/s。识别前先经过MSRCP图像增强后,与原模型相比,改进YOLOv7模型的平均精度均值提高了2.6个百分点,光线遮蔽、藻萍干扰以及稻叶尖形状相似的复杂环境下平均精度均值分别提高5.3、3.6、3.1个百分点,加入ViT分类网络后,较原模型平均精度均值整体提升了4.4个百分点,光线遮蔽、藻萍干扰一级稻叶尖形状相似的复杂环境下的平均精度均值较原模型整体提升了6.2、6.1、5.7个百分点。ViT-改进YOLOv7模型的平均精度均值为92.6%,相比于YOLOv5s、YOLOXs、MobilenetV3-YOLOv7、YOLOv8和改进YOLOv7分别提高了11.6、10.1、5.0、4.2、4.4个百分点。研究结果可为稻田复杂环境的杂草精准识别提供支撑。

不同施肥与耕作方式对高粱-玉米轮作田杂草多样性的影响

为明确改变施肥和耕作方式是否可有效控制高粱-玉米轮作体系中高粱田杂草发生,破解高粱对除草剂敏感、易产生药害和专用除草剂产品匮乏的难题,选择山西农业大学高粱研究所东白试验基地长期定位施肥田和修文试验基地长期不同耕作方式田,于2017-2021年运用群落生态学方法研究5种施肥方式(不施肥、NPK配施、PK配施、NP配施、NK配施)和3种耕作方式(传统耕作方式:秸秆粉碎还田+秋旋耕;秸秆粉碎还田+深松;秸秆粉碎还田+深耕+秋旋耕)对高粱-玉米轮作体系高粱田杂草多样性的影响。结果表明:不同施肥田和不同耕作方式高粱田分别可统计到12种和9种杂草,且均以藜、水稗和反枝苋3种杂草密度较高;不同施肥处理以NPK均衡施肥和NP处理杂草密度最低(同不施肥相比杂草密度分别下降79.18%和76.97%),但对杂草群落多样性指数影响较小同对照相比差异不显著;各施肥处理连续施用3年后的杂草密度大小依次为CK>PK>NK>NP=NPK;3种耕作方式中以秸秆粉碎还田+深耕+秋旋耕处理杂草密度最低(同传统耕作相比杂草密度下降68.48%),且杂草群落构成与其他耕作方式相比相似性较低,但对多样性指数影响较小;较优施肥和耕作方式处理对杂草的强选择压力形成均为连续实施3年后。因此,推荐秸秆粉碎还田+深耕+秋旋耕和NPK(速效钾含量<200 mg/kg地块)或NP(速效钾含量>200 mg/kg地块)为高粱-玉米轮作体系高粱田杂草物理防治较优处理方式。

植保无人机喷施封闭除草剂对稻田杂草的防效研究

为探究植保无人机喷施除草剂对直播稻田杂草防效,采用50%丁草胺乳油、26%噁草酮悬浮剂、350 g/L异噁草松微囊悬浮剂、300 g/L丙草胺乳油4种封闭除草剂,在飞行高度2 m和3 m,用水量22.5、45.0 L/hm^(2)条件下设置不同处理,考察播前施药结合水层管理及播后干封对水稻安全性及对直播稻田不同种类杂草的防除效果。结果表明,26%噁草酮悬浮剂2个用水量处理的成苗率和苗高显著低于其余处理,播后30 d各处理水稻分蘖数均显著高于空白对照,各处理5株苗茎基宽与空白对照无差异。药后15 d,3种除草剂供试浓度下高用水量处理对稗草、千金子、多花水苋、异型莎草等杂草的防效均优于低用水量;播前水封与播后干封效果整体上差异不大。药后40 d,整体上各处理防效均降低,26%噁草酮悬浮剂、350 g/L异噁草松微囊悬浮剂在高用水量时对稗草的株数防效显著优于低用水量,3种药剂在高用水量时对千金子的株数防效均显著高于低用水量,鲜重防效与株数防效趋势基本一致。3种药剂不同飞防参数下对异型莎草和多花水苋的防效有差异,且效果较差。同一药剂在用水量45 L/hm^(2)和飞行高度3 m时对不同杂草的防效优于用水量22.5 L/hm^(2)和飞行高度2 m处理。不同除草剂对不同种类杂草的防效存在差异,高用水量播前施药结合水层管理对不同杂草的防效均优于播后干封处理。后期应适时进行茎叶处理,以提升施药对田间杂草的治理效果。

贵州烟田杂草防控除草剂筛选与安全性评价

为了解贵州烟田杂草种类,筛选安全高效的杂草防控除草剂并评价其安全性,调查贵州烟田杂草的危害状况,评价8种除草剂(960 g/L精异丙甲草胺EC、480 g/L嗪草酮SC、30%草甘膦AS、81.5%乙草胺EC、30%二氯吡啶酸AS、20%敌草快AS、108 g/L高效氟吡甲禾灵EC和36%草铵·草甘膦AS)对烟田杂草芽前和茎叶处理的防效及烟草的安全性。结果显示,烟田共有杂草26科43属49种,以蓼科、菊科和禾本科杂草种类居多,常见有尼泊尔蓼、藜、野苋、繁缕、荠菜、牛膝菊、马唐、稗和香附子等9种。供试除草剂表现出不同的杂草防控效果,其中乙草胺、精异丙甲草胺和嗪草酮芽前土壤封闭处理及草甘膦、草铵·草甘膦、敌草快和嗪草酮芽后茎叶处理对烟田杂草群体的防效在90.41%~97.71%,二氯吡啶酸和高效氟吡甲禾灵对杂草防除具选择性,分别对菊科和禾本科杂草有一定的防效。乙草胺和精异丙甲草胺以推荐剂量进行土壤处理时对烟草安全,但高倍剂量会产生药害;高效氟吡甲禾灵、草甘膦、敌草快和草铵·草甘膦在定向喷雾杂草茎叶时对烟草相对安全;嗪草酮和二氯吡啶酸土壤处理和茎叶处理均对烟草产生严重药害。综上所述,精异丙甲草胺和乙草胺适合在推荐剂量下用于土壤封闭处理控制草害,高效氟吡甲禾灵适用于茎叶处理防除禾本科杂草,草甘膦、敌草快和草铵·草甘膦可用于烟田垄间严格定向喷雾杂草茎叶防控除草,嗪草酮和二氯吡啶酸不适用于烟田杂草防除。